Perinatal HIV transmission substantially contributes to infant and child morbidity and mortality in sub- Saharan Africa. In Malawi, the prevalence of HIV is about 30% among pregnant women and the infant mortality is more than 100 per 1000 live births. Use of antiretroviral drugs has substantially reduced HIV mother to child transmission (MTCT). For example, in the U.S. use of a full (during pregnancy, intrapartum and postpartum) regimen of zidovudine (ZDV) reduced MTCT of HIV by 67%, and in Thailand a shorter (during late pregnancy and intrapartum) regimen of ZDV therapy reduced perinatal HIV transmission by 50%. A more practical and less expensive regimen on nevirapine (NVP) intrapartum to the mother and to the neonate reduced MTCT of HIV by about 50% in a breastfeeding population in Uganda (HIVNET 012). However, some barriers such as counseling and testing need to be overcome to widely implement even this simple regimen of oral NVP. Not all women attend the antenatal clinic, they arrive late to the labor room for delivery, and they do not know their HIV status. Therefore, there is no adequate time to counsel and test women prior to delivery to administer NVP at onset of labor. The purpose of the proposed AIDS-FIRCA study is to determine in a traditionally breast-feeding community in Malawi if a short prophylactic regimen of oral NVP and ZDV given directly to the baby at time of birth reduces the rate of MTCT of HIV. In this randomized clinical trial women who consent to join the study based on their attendance to the labor room (early or late presenters) will receive intrapartum NVP. Their babies will received oral NVP and will be randomized to receive or not receive ZDV for a week. MTCT of HIV will be estimated at birth, 6 weeks, 12 months and to 24 months. These analyses will determine if this simple regimen reduces MTCT of HIV at these time points. The results of this study could have major policy implications. Adequate research infrastructure is available on site to support this study. [unreadable] [unreadable]